Telephone system.



W. W DEAN. TELEBHONE SYSTEM. APIPL'IQATION FILED JULY 31, 1909.

980,613. I Patented Jams, 19.11.

(9, 63/] WILLIAM-W DEA/V along time efforts have been'made to ac 1 UNITED sTATEs PATENT OFFICE.

WILLIAM WrDEALT, or-nLvnIn, oiiro, AssIenoR TO THE DEAN ELECTRIC coivn m.

* Y f or ELYRIA, om n coRronATIoNor 01110.

To all whom it may concern:

Be it known that 1, WILLIAM- W. DnAiv a citizen of {the United Statesfresiding at ,Elyria, 1n the county of Lorain and State. of -.Oh 1o,,ha.ve invented certain new and useful I the vart to which it appertains to make and use the same I.

" My invention rela'tes mo-re particularly talking circuits. and receivers therefor; one of the ob ects belngto combine thereceiver n coil and'thejinductorium. The advantages realized by such anfarrangement will be ap-' parent. to those skilledi'n this art.' Among them are the reductidn of cost, the compact- I nessof the apparatus,and the reduction of the impedance'in the talking circuit. yF'O-lf complish (this in a successfully operativesubstation circuit,- but. heretofore such, ef-

forts have been only partiallyrealized. I-

have'combined 'their use with a receiver core, having a [very low reluctance, and a highly efiicient magnetic circuit. 'To' do -c1ently high resistance are used, a permathis have used a flux conductor construct-J ed of soft iron E-shaped laminations' fas-Y tene'd togetherf After long and exhaustive testsI find'thatsuch an arrangement effects the phrpose desired. By soft iron I intend. to include those irons and'steelswhich have a high magnetic permeability. As a matter of fact, a soft steel is generally used, though in magnetic parlance, -soft ironisgenerallyusedto indicate a metal having-ahigh permeability. By constructing this core .of

- such material and. by laminating it, I so lower the reluctance and hysteresis that- I- may greatly reduce the number of turns in the receiver coil iwithout'deducting from the effect upon the diaphragm. The, reduction in the number 'of turns on the receiver lowers th'eresistance thereof so that a larger. flow of current for the s'amevoltag'e will traverse the circuit. This curren't'will initially magnetizep the receiver, servingithe purposes of a permanent or biased magnet, thus obviating the necessity for'high reluc tance hard iron cores. Asa result of this larger flow of current, I may greatly reduce the turns of the coils of the inductorium. 'Soft iron cores of the prior art have not been of such low reluctance asto realize TELEPHONE SYSTEM.

H Specification of Letters Patent. Patented J 3,1911; Application filed my a1 1909. Serial No! 510,620.-

these-advantages, while the hard iron cores used for this purpose, have been of such high 'reluctance as to make them impractical for the cores of inductoriums. I, haveth'us' Produced a receiver which, among other thmga reahzes the good points of a per1na= nent magnet receiver and at the same'time employs a core which is practical for the same use inan 'inductorium enabling 1116110 combine these coils.

My invention in taken in eonnection'with the accompanying illustrations showing one specific embodiment thereof, while its scope will be more particularly pointed out inthe appended claims. f

Figure l is of a substation circuitshowing my invention, Fig. '2 is' an end.- lelevation of-the coin-f bined receiver and induct'orium; with the diaphragm removed.

1 and 2. are the'leads of the line entering the substation. A bridge 3 containing the signaling device S terminates in' the contact 4 which cooperates with the switch hook'H to complete the bridge. If signals of sutfisoft iron laminated receiver core is shown.- at 10. This core isbuilt, of insulated laminations, and in the form illustrated, consists of substantially, E-shaped punchings fas-- tened together to form a base .lfiand three limbs 11, 12 and 13 perpendicular thereto. On one of these limbs, as at 12, a coil 14 is wound which operates both as a receiver coil and as'the inductorium. The second line bridge contains this coil, the transmitter T, and a local battery B. From a point 9 of'the" coil 14 a conductor 7'leads to the up- "per' contact .5 of the hook H. The hook H also controls the second bridge at the upper contact 6. The receiver diaphragm is shown, at 15. When the hook Hiis down, the 'talking instrument is disconnected and'the signal circuit comple'ted- Th 'ocal transmitter circuit is traced throng Tlf. B .8'6-H' 5 7 14. to T.

' The operation of the dev 3e will notmake a detailed description't-hereof;

ll be best. understood by" reference to the following description whenwill'be readily understood by those skilled in the art and I I a diagrammatic illustration may use any form which will accomplish. my purpose. .numerous and extensive departures from the Itiwill also .be apparent that form and details of the apparatus may be made without departing from the spirit of the invention, "solely for the soft ironpunchings,

the same being herein shown one specific embodiment thereof.

Claims. .j

1. In a telephone system, a telephone line, a bridge of said line, an inductorium in said bridge, a laminated soft iron core, a plurality of laminated flux conductors integral with said core, a coil in said line bridge wound on said core,

ceiver winding,

a connection dividing said coil, 2. portion of said coilserving as one winding of an inductorium in one of said branches, a second portion of 'said coil serving as the other winding of said'inductorium in a second branch of said bridge, and a transmitter and source of current in one of said branches in series with one of said windings. 1

2. In a telephone system the combination of a telephone line, abridge of said'line, an inductorium in said bridge, an E-shaped fiuX conductor constructed of a plurality of a coil mounted upon one of the limbs of said flux conductor and connected in saidbridge, said coil serving as a receiver winding, a connection dividing said coil, the part of the coil on one side of the connection serving as one winding of the inductorium, the second part serving as the purpose of clearly illustrating an inductorium,

said coil: servingas a reother winding and a transmitter and source of current in series with one of said windings. In a telephone system, the combination of a telephone line, a divided bridge of said line at a substation, areceiver coil divided into two parts, said divided ,bridge being united at the point of division of the c011, one of said parts serving as one winding of a second winding of the inductorium, a source of current and a telephone transmitter connected in 'series in one of the divisions of the bridge and a flux conductor upon whichsaid coil is mounted, built up of a plurality of soft iron E-shaped members.

4:. In a telephone system, the combination of a telephone lines, a divided bridge of said line at a substation, an inductorium in said bridge, a laminated soft ironcore, a plurality of laminated flux conductors integral with said core, a coil in said line bridge wound on said core, said coil serving as a receiver winding, a connection dividing said coil, aportion of said coil serving as one winding-of an inductorium in one of said branches, a second portion of saidcoil serving as the other-winding of said inductorium in a second branch of said bridge and a transmitter and source of curren't'in said bridge in circuit with said inductorium.

In testimony whereof I afiix my signature inpresence of two witnesses.

, WILLIAM w. DEAN.

1 Witnesses: i

' F. O. RIGI-IEY,

C. A. SEvnncoeL. 

